1. Field of the Invention
The present invention relates to a method for data traffic management in a communication network. The present invention further relates to a datacenter and a communication network.
2. Description of Related Art
A communication network includes a plurality of network nodes which are suitably connected with each other via wired or wireless links. Messages from a source node to a destination node are routed through switching nodes (or routers or switches) of the communication network using a routing protocol such as TCP/IP. This TCP/IP protocol where TCP and IP stand for Transmission Control Protocol and Internet Protocol, respectively, is widely used for data communication via the internet. The present invention relates in general to communication networks and in particular to so called Ethernet communication systems according to the IEEE 802 DCB standard, aka CEE. Hereinafter, the present invention and its underlying problem are, therefore, described with regard to such Ethernet networks using TCP/IP; it being noted that it can nonetheless be applied to other communication networks as well.
In a communication network, a many-to-one data communication is a basic requirement. A source node transmits data in the form of a plurality of data packets or short packets to a switching node. The switching node receives and transmits each packet to a specific destination node based on the address in the header of the specific data packet. However, if one or more destination nodes stop responding and/or slow down, then the switching node suffers from hogging and blocking. This leads to the creation of a phenomenon (i.e. data transmission capability is going down) which can be represented by a so-called saturation tree. The present application addresses the efficient use of existing resources of such a communication network.
Hereinafter a hotspot of a data communication (also known as bottleneck or points of congestion) describes an abstract entity such as an event or a location describing the effect of the communication demands data rate or data stream which exceed a current communication supply. A hotspot is a communication phenomenon where the performance or capacity of the entire communication network is limited by a single or limited number of components or resources. If one or more hotspots are present a backlog in the data communication is generated. If within a communication network multiple inter-correlated hotspots are present, a saturation tree is generated which somehow combines the backlog effect of the set of inter-correlated multiple hotspots.
One reason for the slowing down of the data transmission, the creation of hotspots and saturation trees is the so-called data congestion. In today's communication networks, data congestion may occur when a switching node or destination node receives more data packets than it is able to process. Data congestion may also occur when data packets should be transferred from a faster to a slower transport element or portion of the communication network. In this regard, the corresponding network nodes and the slower transport elements or portions are forming a kind of a bottleneck of this data communication. In order to avoid these data congestions or bottlenecks, modern communication networks include congestion control approaches to achieve high performance of the data traffic through the different nodes of the communication network. These congestion control mechanisms are used to control the rate of data entering the network, keeping the data stream below a certain data rate that would trigger a collapse.
For example, US 2007/0070901 A1 discloses a method and a system for congestion management for converged network interface devices.
Recent trends illustrate a shift from large main frame computing to commodity classes of service in datacenters. Datacenters (also known as center networks) are facilities for housing several computer systems and various components associated with the computer system. Datacenters are especially a collection of computing, storage and/or memory nodes which are interconnected via a (communication) network, such as a network in a fat tree topology. For example, a typical datacenter may include in addition to a computer or a server system, other devices and facilities such as backup power supplies, backup data communication connections, environmental controls, security components and the like. Those datacenters can be connected with the Ethernet or internet using TCP/IP protocols. Future datacenters will therefore focus on internet and Ethernet compliance for example for blade clustering, storage, LAN-application, etc. Data congestion, however, still remains a basic problem with datacenters.
Hence, it is a challenge to improve the traffic and data management with regard to data congestion in modern communication networks.